Re: [ferret_users] time axis limits with DES files?

[Ansley Manke <ansley.b.manke@xxxxxxxx>]

Hi Andy,
It's not a hard limit. The only limit with descriptor files is the number of stepfile datasets listed (5000, which is the total number in all the descriptor files open in a session).  

For anyone who doesn't know about it, a helpful link in the Ferret docs is the "program limits" table, found in the index under "limits, Ferret program limits":  http://ferret.pmel.noaa.gov/Ferret/documentation/users-guide/Grids-Regions/FERRET-PROGRAM-LIMITS#_VPINDEXENTRY_732

I was able to create a set of small example files with 13 years of 3-hour timesteps:

define axis/t=1-jan-2000:31-dec-2012:3/units=hours threehour

let var = t[gt=threehour]
let npts = `var,return=lsize`

repeat/L=1:`npts`:8 (def sym name = var_`l`; \
if `l lt 1000` THEN def sym name = var_0`l`; \
if `l lt 100` THEN def sym name = var_00`l`; \
if `l lt 10` THEN def sym name = var_000`l`; \
save/clobber/file=($name).nc/L=`l`:`l+7` var)

then use make_des with all of these. Ferret then sees all 37985 steps in the resulting descriptor dataset, and "plot var" shows the whole time range.

When you use your descriptor set, does "show grid" give the right number of timesteps?  Do you see any error messages?

On 4/17/2014 7:45 AM, Andy Jacobson wrote:

Hi,

I'm using Andrew Wittenberg's make_des perl script to make a long time series from a bunch of netCDF files.  I have 4750 daily files, each with eight 3-hourly timesteps, everything uniform and CF-1.x compliant.  The DES file correctly lists all 4750 of the files, but when I use that DES file within ferret, ferret only sees the first 9440 time steps.  This 9440 number persists even when other nx/ny/nz grid parameters change.  Have I stumbled upon an internal limit within ferret, or is something else going on here?

I'm using ferret v6.82, on linux.

Thanks,

Andy